Thermostatic oven-heat regulator



Aug. 23 1927. Y

B. E. MEACHAM 'THERMOSTATIG OVE HEAT REGULATOR Filed Nen/.16, 192e Il l PatentedlAug. 23, 1927.

UNITED STATES PATENT OFFICE.

BENJAMIN EDWARD MEAGHAM, F LORAIN, OHIO, ASSIGNOB TO AMERICAN STOVE COMPANY, OF ST. LOUIS, MISSOURI, A CORPORATION OF NEW JERSEY.

THERMOSTATIC OVEN-HEAT REGULATOR.

so construct the parts that the said housingcan be made of a cross section considerably 'less than 1s requiredl 1n the said patent, and at the same time make a device that is simplein construction, durable, long lived in,v

operation, aswell as occupying considerably less space. y

In carrying outfthe above ideas I- have utilized a structureJ that has many novel features that will be' pointed out hereinafter.

In the accompanying drawings:

Figure y1 is -avertical longitudinal sec-l tional view of a thermostatic heat .regulator 'embodying my improvements, said gas valve being shown in open position. f Figure 2 is a sectional view similar to Figure 1, with the exception ofthe parts and the gas valve actuated thereby are shown in their closed positions.

Referring now to the drawings in which similar reference characters denote the same parts, 1 is a vertical tube, whichl in the present instant is composed of a round gas pipe member-,that'has its ends 2 externally screw threaded, and receiving the inner ends inghead 4 screwed in position on the respective ends of the housing 1'. This member 1 is preferably composed of a gas pipe y that in full size is about one inch in external diameter.

Extending vertically within the` ,housing 1 is a vertical lever 5 that consists `of a round lmember having its lower end 6 reduced and passingl through a vertical opening 7 formed 0 in a slightl enlarged portion of the valve stem 8. Tli'is housing 4 has at the oven side of the housing a nipple 9 or other similar device attached, the said nipple adapted to feed gas to the oven burner (not shown).

The ,upper end 10 of the lever 5 is pref` of an upper casting head 3 and a lower cast'- Application led November 16, 1926. Serial No. 148,651.

erably made of a separate `piece screw threaded :to the said member as at 11. This member 10 extends upward into the top housing 8, its upper end 12 spanning ashaft 13 and coacting with the said shaft in a manner to be presently explained. i

A copper tube'14 has one end fastened or anchored to the head 3, and extending within this anchored end of the tube is a second tubular member 16, the outer end of the meinber being open. Passing through the copper tube 14 is a porcelaimor-other substantially non-expansiblemember 17. One end of thisV porcelain member engages a cap 16 closing one end of said tube and the other end of the porcelain member 17 engages the closed end 1 8 ofthe member 16. It is well understood by those skilled in this art that the copper tube expands and contracts as it is heated and. cooled. As the copper tube 14 expands, the porcelain member movesoutward in respect to the head 3, and as the tubular member` contracts, the porcelain member moves inward, moving with it the tubular member 16. The expanding and contracting, therefore, lof the copper tube causes the end 18 to push inward against a bulged portion 19, allowing the said member to follow its movement, and

when the copper tube contracts, then the porcelain member pushes the end 18 against the bulged portion, movingthe member 10. A spring actuated member or cup 20 is located in the wall of the head 3 opposite to the said copper tube 14 and also the porce- -lain member 17 and between the porcelain member and the upper head portion 12. This member .20 is normally pushed inward bya suitable coil spring 21, and engages a slightly outwardly bulged portion 22, the said bulged portion carrying an outwardly extending pin 23 that passes through the inner end of the member or cup portion 20.

The shaft 13 has its inner end 24 screw threaded into the head "3, the outer end of the said screw threaded portion being closed by a suitable screw 25. The opposite or outer end of the shaft 13 carries a suitable wheel 26-by means of which the shaft 13 is rotated in the said head 3 and the shaft caused t0 move endwise by being rotated in a manner which will be presently explained.

Referring now to the valve stem 8, it is provided at its inner end with a tapered valve 27, its opposite end 28 projecting into an opening 29ormed in a plug 304 that serves 'to guide Iandlmit it 'for a purpose that vwill be referred .toi presently. The opposite valve end 27 coacts with an". opening 31' for regulating and controlling the amountof gas'passin through the'nipple'9.'v n op'erat'on-`v gas-1s' vpre 'l 'housing' 1 -through an `opening .32ythat 'is .formed in'its upper end, a pipe' (not shown) being screw threaded into the said opening;- `For th'e'pu'r'pose ot explaining theioperation ofA this construction, (in Figure 1, I have `shown the .wheel 26 adjusted to the v55DTtem1 'peratlre fmark, and the remaining parts bef i115' in their .corresponding positions. `It w' l `be vobserved that. when-thewheelv so adjusted, thel part 33 'i'sf out of engagement v vitl1'-theV inner surface Slot the upper extremity or' head 12 ofthejlever 5.y When-in .2Q this position gas freely' passes through the "5"'nipp1e. 21 for eating theoven i(not shown). Asthe ovenis being heated, the eopp'ertube 14-eXpands,or lengthens and-the' porcelain member 17 @moves inward withthe said eic-V Ipan'sion tube 14. It moves inward until the ""s'urface 34. andits head'. 12 is in'. contact with the' part 33 of the s'haftlS,A at which time the expansiontube -l4'eontinue's vand the said spring aotuated member -20 forcestheparts 3Q' "'ii1't'o 'the position shown" in Figure 2, namely 'with the 'valve' 427 closingthe -nipple .opening 31 and cutting'tlie 'gas olf', When: the foven l f cOolsy a little, then thegco'ntraetion of the Copper l tube ,14 forces the'porcelain` member 171 3 5'- inward, 'moving Ythe'saidflever i5 so a'sjto open `Ythe nipple` open-ing 31,1. thus permitting` gas again'tOflOw tothe burner ",withinV the 'said oven, Athereby lmaintaining the heat in 'thel oven tothe" degree to'V which vthe." device is set, Vizi 550 v1,-v with the outer end ofthe valve'stem'S'l againstthe wall of'theppeningf29. In'order' `the-spring actuated member V 20 is pus ed in- Ward,`thus 'Carrying th'e'head 12 outl of en gagement with thepart 330i' the Vshaft 413.'

`lir'oi'n-.the foregoing it `willbe observed that' the -valve`27 is'al'ways wide 'openluntilja comN so tact'` is madefbetween the surfaee'. and the part 33 ofthe'shaft `13an`d 'no' movements'of 'the valve will .take untilf-:thiscontact ismade. "Inthis operation fthe spring actu*- ated member 20 is vtheelosing o means', and" the, contrae-tion ofA the lcopper' "tubejis', the

e'r'ably fed' to l the'.

nagement withy thet 1s openin mean's'forI the said'valve, thuselos- -ing` .o and permitting the flow ofV gas through the nipple.v

From the foregoing description the op.er' yation of the' mechanism for 'controlling the 70 flow 'of gasthr'ough the nipple andl thereby controlling the flame "of thelburner in thev oven also'controls' theheatof theY oven. By rsetting.; the 'wheel 26136 anydesired degree on its edge denoting a certain degreeo heat', 75 'then the heat in-the oven' will-be' controlled to that'de ree..' A' Y Il ft. will @noted fromthe' f'oregoingi de` 'scrption thatin a sense .thepart' may aptly be referred to asa 'loatingfulcrunL-to By this' is meant that it 'does` no 't act' as a ulcrum' until 'the surface 3.4 off the head1 i2 l is brought into contactwith-it due to the'e# pension of the 'co ,per tube 14.

In .F'gure- 1;'t' e regulating Q'wheel' 26 4is S5. u set at 550 to'which the pointer '26v is pointed. Thisregulating. Wheel is provided 'with 'a stop 28"v -that 'is adapted to engage the" Lp'ojnter' 265V which will preventjthe' wheel from'being continuouslyv rotated and thereby .9 0

1 thrown out of adjustment.` The 'wheel 26 in Figure 2 is set .at the'same temperature as itis in Eigure '1 butinFigure 2r the heat of .the oyen'is raisedto-t'he temperaturefof 550,

- It' should be understood that :variations1 and changes maybe lmade- 'in the construe `tion .herein'de'scribedand shown, solong;

asthe changes -donot' take` the construction -Aoutside of a air'interpretationwof. the ap- 1,00'

pended claims.l

f Havin'gftlfus ldescribed my invention, what desire to'pclaimfand securefby Letters Patent ofth'e United States is: d. A `thermestatio ``oven heat regu 4c'o'rnprisi ng Va movable lever, a fuel-valve A'operatively-eonnectedwithone. end of the I lever, av thermostatie' element' engaging the said v leverxnear its op osite e'nd, a`fulcrum-'`v located Abeyond t'he` saidlthermostatic mem-f 31"" ber, 'the endl of said leverV adapted to engage' .the sai-d. fule'rum,' and means .located be- `tween the vfulcrum*and the said `th'ermostatie member, said means constantly pressing the 1 adapted to press' the 'end of the lever against said'fulcrum.j l r Y Y' Y 2. 'A "thermostatioL oven. heat regulator' ico'mprising'a housin i'having at-one fend 4a 'uelQutIet,'alever 'wit in thesaid housing, ar 120' fuel valve adapted 'to clo'se the 'said'outlet x said fuelva'lvec'onneoted with one end 'of the said lever;a-"thermostato"member llocated. adjacent the loppos'lte end of said' lver'- 'and 'engaging'Iy it, an adjustablel fulcrum adapted 125 f toengage thelever beyond lthe' thermost'atic member'iand a pressure device located b e' tween said vfu'loru-m and said Athermostatio' vmember,causing thesaid lever to follow the' .movement ofthe thermo'stat,'and causin'gthe 130 lever against the -thermostatic member' and .1115" end of the lever to engage the said adjustable fulcrum for the purpose specified.

3. A thermostatic oven heat regulator comprising a housing, a lever located in the said housing, the housing having a fuel outlet, a fuel valvelocatedin the housing-and adapted to open and close saidoutletfone end of the lever operatively connected with the fuel valve, an adjustable fulcrum located beyond thel said thermostat and adapted to engage the same side of the lever as the thermostat, and a spring actuated memberlocated at the opposite sideof the lever and engaging it at a point between the thermostat and the fulcrum, the parts operating as specified.

4. A thermostatic oven heat ref ulator comprising a housing, a fuel outlet located in the said housing, a movable element having one member connected with the said fuel valve, a thermostatic member engaging said element near itsopposite end, an adjustable fulcrum adapted toengage the same end of the element, and pressure means engaging the element between thei-thermostatic member and the fulcrum and' pressing said element towards both the last mentioned elewith the fuel valve, a thermostatic member engaging the opposite end of said lever and on-the same side as the fuel valve, the fuel valve having a stem portion adapted to engage the said housing for limiting its opening movement.

6. A thermostatic oven heat regulator comprising a housing'having Va fuel outlet,

va fuel valve cooperatingwith"the-outlet, a f

lever having one end connected with the fuel valve, a thermostatic member engaging the side thereof as the fuel valve, an yadjustable fulcrum adapted to engage the end of thev lever adjacent the thermostatic member and on the same side as the thermostatic member,

a pressure device located on 'the opposite side of the lever and pressing it against the thermostatic member and towards said fulcrum, and means limiting the opening movement ofthe said valve, the parts operating as de-v scribed.

7. A thermostatic oven heat regulator on the opposite side of said element, and an adjustable memberadapted tobe engaged by the remaining element, wherebythe parts are adapted to operate in the. manner described. j

In testimony whereof vI hereuntoaifx my signature. l

a BENJAMIN EDWARD MEACHAM.

l 45 opposite end of the lever and 011 the. Same 

